Abstract

To directly compare the stressor capabilities of adenosine and high-dose dobutamine/atropine using first pass myocardial perfusion magnetic resonance imaging. Fourty-one patients with suspected or known coronary artery disease underwent cardiac magnetic resonance (CMR) perfusion imaging at 1.5 Tesla on two consecutive days prior to invasive coronary angiography. On day 1 a standard CMR perfusion protocol during adenosine stress was carried out (adenosine infusion with 140 μg/kg/min, 0.1 mmol/kg Gd-DTPA). On day 2, the identical CMR perfusion sequence was repeated during a standard high-dose dobutamine/atropine stress protocol at rest and during target heart rate (85% of maximum age-predicted heart rate). Stress-inducible perfusion deficits were evaluated visually regarding presence and transmural extent. Quantitative coronary angiography served as the reference standard with significant stenosis defined as ≥50% luminal diameter reduction. Twenty-five patients (61%) had significant coronary stenoses. Adenosine and dobutamine stress CMR perfusion imaging resulted in an equally high sensitivity and specificity for the stenosis detection on a per patient basis (92 and 75% for both stressors, respectively). Agreement of both stressors with regard to the presence or absence of stress-inducible perfusion deficits was nearly perfect using patient- and segment based analysis (kappa 1.0 and 0.92, respectively). Adenosine and dobutamine/atropine stress CMR perfusion imaging are equally capable to identify stress inducible deficits and resulted in an almost identical extent of ischemic reactions. Though adenosine stress CMR perfusion imaging is widely employed, dobutamine stress CMR perfusion represents a valid alternative and may be particularly useful in patients with contraindications to vasodilator testing.